Safety attachment for water-heating apparatus.



J. P. CUNNINGHAM.

SAFETY ATTACHMENT FOR WATER HEATING APPARATUS. APPLICATION FILED JULY 14,1913

1,089,624. Patented Mar. 10, 1914.

tlhllTEU hTATES PATENT OFFICE.

JOHN F. CUNNINGHAM, OF SPRINGFIELD, MISSOURI.

SAFETY ATTACHMENT FOB, WATER-HEATING APPARATUS.

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To all whom it may concern Be it known that 1, JOHN F. CUNNING- HAM, a citizen of the United States, residing at Springfield, in the county of Greene and State of Missouri, have invented certain new and useful Improvements in Safety Attachments for VVater-Heating Apparatus; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in safety attachments for water heating apparatus.

One object of the invention is to provide an attachment of this character whereby should the expansion pipe or overflow pipe from the expansion tank, become stopped up or clogged from any cause the pressure in the pipes and boiler of the apparatus will be relieved after reaching a predetermined point, thereby preventing the pressure from bursting the boiler or pipes.

Another object is to provide an attachment of this character having means whereby an alarm or signal will be automatically operated when the pressure in the apparatus has been relieved by the attachment, thus in dicating that the regular relief or expansion mechanism of the apparatus is defective.

A further object is to provide an attachment of this character which will be simple, durable and inexpensive in construction, eflicient and reliable in operation and which may be attached to any flow or return pipe of the heating apparatus.

With these and other objects in view, the invention consists of certain novel features of construction and the combination and arrangement of parts as will be more fully described and claimed.

In the accompanying drawing is shown a diagrammatic view of the attachment, parts being in section.

In the embodiment of the invention, I pro vide a mercury chamber 1 in the form of a closed tank or vessel of suitable size and which preferably has its bottom inclined from its outer edge toward the center and has in the lowest point of its bottom a discharge opening to which is connected an upwardly projecting relief pipe 2. The tank or vessel 1 preferably has on its lower end an annular flange or base 3 which holds the chamber 1 spaced above the support on which the same Specification of Letters Patent.

Application filed July 14, 1913.

Patented Mar. 10, 1914-.

Serial No. 779,035.

rests thereby permitting the pipe 2 to pass beneath and to be connected with the opening in the bottom of the tank as shown. The flange 3 is provided with a notch or opening 4. through which the pipe 2 passes. The tank 1 is connected at its upper end by a branch pipe 5 with any of the flow or return pipes of the heating apparatus, but said pipe 5 is preferably connected with the apparatus near the boiler.

Arranged in the relief pipe 2 at a suitable elevation is a separating chamber 6 which is also preferably provided with a concaved bottom to the center of which is connected the lower portion of the pipe 2. The upper portion of the pipe 2 is connected to the top of the separating chamber 6 and extends above the same for a suitable distance after which the upper portion of the pipe 2 eX- tends laterally at right angles and thence downwardly and has its open end disposed above a water receptacle 7 the purpose of which will be hereinafter described. The receptacle 7 is connected to one end of and suspended by a damper operating chain or cable 8 which passes over suitable guide pulleys 9 and is connected at its opposite end to the check damper 10 in the smoke pipe of the boiler furnace as shown. The weight of the receptacle 7 is substantially the same as the damper plate 10 so that these parts normally counter-balance each other and the damper remains in closed position. The receptacle 7 is preferably provided with a spigot 11 by means of which the contents of the receptacle may be drawn off when desired.

Secured at a suitable position on the receptacle 7 and preferably at the bottom thereof is a depending circuit closing rod 12 having on its lower end a head 13 and which is slidably engaged with a guide bracket 14c secured to any suitable support. Spaced a suitable distance below the head 13 on the rod 12 is a shelf 15 on which is disposed an electric switch which is preferably in the form of a push button 16 an ranged in an electric circuit 17 having therein an electric bell 18 which may be located at any desired position in the building.

In the operation of my improved safety attachment it will be seen that should the overflow pipe from the expansion tank or any of the other pipes of the heating apparatus become clogged or stopped up from any cause so as to interfere with the expansion of the water in the boiler, or pipes When a fire is made in the boiler furnace, the pressure of the expanding water will force the mercury in the chamber 1 out through the lower end thereof and up through the relief pipe 2 into the separating chamber wherein the water will be forced through the mercury and will escape through the upper portion of the relief pipe :2 and discharge intothe receptacle 7 thus relieving the pressure in the pipes and boiler of the apparatus and preventing the bursting of these parts. As soon as sufiicient water has been discharged into the receptacle 7 to overbalance the weight of the damper plate 10, the latter will be swung open to a greater or less extent, thus checking the fire in the boiler furnace and reducing the temperature of the water. As the receptacle 7 lowers under the weight of the water discharged therein the head 18 on the circuit closing rod 12 will be brought into engagement with the switch or push button 16, thus closing the electric circuit 17 and sounding an alarm which will indicate to the occupants of the building that there is a stoppage in the expansion pipes or tank of the apparatus. After the alarm or signal has thus been sounded and the stoppage of the pipes made known to the occupants of the building, the water may be drawn from the receptacle 7 through the spigot 11 and the receptacle again raised and supported in position by the Weightof the damper plate as will be readily understood.

From the foregoing description taken in connection with the accompanying drawings, the construction and operation of the invention will be readily understood without requiring a more extended explanation.

Various changes in the form, proportion,

and the minor details of construction may be resorted to without departing from the principle or sacrificing any of the advantages of the invention as claimed.

Having thus described my invention, what I claim is:

In a safety attachment for water heating apparatus, a mercury chamber adapted to be connected with one of the pipes of the apparatus, a substantially inverted U-shaped relief pipe having one long leg, having a lateral arm connected with an opening in the bottom of said mercury chamber, a separating chamber arranged in the long leg of said relief pipe, a receptacle arranged in position to catch the water discharged from said relief pipe, pulley supports, a check damper arranged in the smoke pipe of the heating apparatus, a flexible element connected with said damper and with said receptacle and passing over said pulleys, whereby the receptacle is counter-balanced and supported in position, an electric alarm circuit, an alarm arranged therein, a switch to open and close said circuit, a circuit closing member carried by said receptacle and having thereon a switch engaging element, and means to support said switch in position to be engaged by said switch engaging element when said receptacle receives suflicient water to cause it to lower and thereby simultaneously open said damper and sound an alarm.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

JOHN F. CUNNINGHAM.

Witnesses:

Brssm A. KNOX, N. M. BROCKUS.

Copies of'this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

